Read Edit View history 奥陶系 àotáoxì Ordovician system Origin Definitions Defs Strokes Stroke Words Sentences Sents created sense approved 奥陶系/奧陶系 · àotáoxì · Ordovician system 2026/03/04 奥陶系 / 奧陶系 àotáoxì Ordovician system the Ordovician system (geological stratigraphic unit) 这里的地层属于奥陶系。 created sense Mar 4, 2026, 02:25 AM